Abstract

Background: Therapeutic drug monitoring (TDM) for immunosuppressive (ISP) drugs is an important component of organ and tissue transplantation and chemotherapy management. Whole blood is the specimen type for the quantitative analysis of cyclosporine A, everolimus, sirolimus, and tacrolimus. Some alternatives to venous whole blood samples have the potential to reduce blood volume requirements and simplify sample collection and transport.

Results: All analytes were found to be linear across the measurement range of 22.7–937.0 ng/mL (18.9–779.1 nmol/L) for cyclosporine A, 2.3–44.2 ng/mL (2.4–46.1 nmol/L) for everolimus, 2.2–47.2 ng/mL (2.4–51.6 nmol/L) for sirolimus, and 2.2–41.3 ng/mL (2.7–51.4 nmol/L) for tacrolimus. Imprecision was evaluated at concentrations within the therapeutic range and was found to be 10.1% and 5.8% for cyclosporine A, 10.0% and 10.0% for everolimus, 15.0% and 11.9% for sirolimus, and 6.8% and 8.5% for tacrolimus. Method comparison (n = 30 for each analyte, using Deming regression) indicated slopes of 1.08, 1.02, 0.90, and 1.15 and intercepts of −12.8 ng/mL (−10.7 nmol/L), 0.8 ng/mL (0.8 nmol/L), 1.5 ng/mL (1.7 nmol/L), and −0.3 ng/mL (−0.3 nmol/L) for cyclosporine A, everolimus, sirolimus, and tacrolimus, respectively.

Conclusions: This feasibility study demonstrates that precision and bias of ≤15% can be achieved for microsampling-based ISP monitoring.

Log in using your username and password

Log in through your institution

If your organization uses OpenAthens, you can log in using your OpenAthens username and password. To check if your institution is supported, please see this list. Contact your library for more details.